The main components of semi-automatic transmissions are conventional and, if need be, also manually actuatable shifting systems, in which the shifting and/or starting clutch between the driving motor and transmission as well as the selection and shifting of gears are actuated automatically using corresponding operating elements. These operating elements are typically configured as hydraulically or pneumatically actuatable piston/cylinder arrangements or electric actuators which act upon an actuating unit for the above transmission functions. The actuating unit can be provided on or in the transmission.
For the actuation of hydraulic or pneumatic operating elements, pressure-generating and control devices are required, which according to the state of the art comprise a hydraulic or pneumatic pump as the pressure-generating device, an accumulator and a hydraulic or pneumatic control unit with control valves and sensors, which are connected to a central control and regulating device and can be actuated by the same based on control and regulating functions stored there.
A drive train is known from DE 102 30 612 A1 for operating a motor vehicle. The drive train comprises a driving motor, a torque transfer system and a semi-automatic transmission. The torque transfer system can be automatically actuated by way of an actuator and the transmission has at least two shiftable gears with different ratios, wherein at least one gear of the transmission is used as the starting gear. A starting process is controlled by a controller using a characteristic starting line, which can be adjusted to a driving situation at least sometimes.
DE 100 31 771 A1 discloses a motor vehicle comprising a device for automatically actuating a clutch. The drive train of the motor vehicle comprises an engine, a transmission, a controller and an actuator controlled by the controlled for actuating the clutch. During a starting process, the torque to be transmitted by the clutch is increased and adjusted substantially to a specified torque value, wherein the torque to be transferred by the clutch is at least briefly increased and then lowered again before reaching the rotational speed uniformity between the engine rotational speed and the transmission rotational speed. In this way, more comfortable starting of the motor vehicle can be achieved.
It is common in semi-automatic transmissions having also semi-automatic clutches that existing functionalities are adjusted to an intended vehicle use with the help of a set of parameters. With the help of the parameter set, the handling can be influenced within certain ranges. It can be set to have more emphasis on comfort or performance. In such an adjustment of the driving behavior, it is always assumed that the components and assemblies considered vary only within sufficiently tight tolerances. The appropriate limits can be included in such an adjustment. If dependencies are known, adaptations or corrective curves can be employed in order to compensate for influencing factors that would change the handling.
The disadvantages of the state of the art are that, despite the manner or procedure mentioned above, during the operating time of a transmission unexpected variances may occur such that the control program with the adjusted parameter set does not result in the desired handling. It is possible that a vehicle cannot start because the programmed parameter set is not suited for overcoming the present driving situation. This can occur if one or more boundary conditions have drastically changed compared to the adjusted state. For instance, the transfer behavior of the clutch can be considerably lower; the engine power considerably worse and/or tractive resistance can be considerably higher.
Therefore the present invention is based upon the objective of providing a method for monitoring a starting process of a motor vehicle and eliminating the disadvantages of the state of the art.
The underlying objective of the invention is achieved by a representative method for monitoring a starting process of a motor vehicle having the characterizing features according to the main claim.